diff --git a/src/config.c b/src/config.c
index 9c99227..617ebe1 100644
--- a/src/config.c
+++ b/src/config.c
@@ -116,7 +116,7 @@ int config_set(Config * config, char const * section, char const * variable,
 #endif
 	if(section == NULL)
 		section = "";
-	if(variable == NULL || string_length(variable) == 0)
+	if(variable == NULL || string_get_length(variable) == 0)
 		return error_set_code(-EINVAL, "variable: %s",
 				strerror(EINVAL));
 	if((mutator = mutator_get(config, section)) == NULL)
diff --git a/tests/config.c b/tests/config.c
index 407c3a5..704ca35 100644
--- a/tests/config.c
+++ b/tests/config.c
@@ -76,7 +76,7 @@ static int _test(char const * progname, String const * filename,
 	if(config_set(config, NULL, variable, "") != 0)
 		ret = -error_print(progname);
 	if((value = config_get(config, NULL, variable)) == NULL
-			|| string_length(value) != 0)
+			|| string_get_length(value) != 0)
 		ret = -error_set_print(progname, 1, "%s (\"%s\")",
 				"Invalid variable returned", value);
 	/* config_set: restore the variable */